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algebraicIndependent_of_finite' (s : Set A) (hinj : Injective (algebraMap R A)) (H : ∀ t ⊆ s, t.Finite → AlgebraicIndependent R ((↑) : t → A) → ∀ a ∈ s, a ∉ t → Transcendental (adjoin R t) a) : AlgebraicIndependent R ((↑) : s → A) := algebraicIndependent_of_finite_type' hinj fun t hfin h i hi ↦ H _ (by rintro _ ⟨x, _, rfl⟩; exact x.2) (hfin.image _) h.image _ i.2 (mt Subtype.val_injective.mem_set_image.mp hi)
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
algebraicIndependent_of_finite'
Variant of `algebraicIndependent_of_finite` using `Transcendental`.
sumElim_iff {ι'} {y : ι' → A} : AlgebraicIndependent R (Sum.elim y x) ↔ AlgebraicIndependent R x ∧ AlgebraicIndependent (adjoin R (range x)) y := by by_cases hx : AlgebraicIndependent R x; swap · exact ⟨fun h ↦ (hx <| by apply h.comp _ Sum.inr_injective).elim, fun h ↦ (hx h.1).elim⟩ let e := (sumAlgEquiv R ι' ι).trans (mapAlgEquiv _ hx.aevalEquiv) have : aeval (Sum.elim y x) = ((aeval y).restrictScalars R).comp e.toAlgHom := by ext (_ | _) <;> simp [e, algebraMap_aevalEquiv] simp_rw [hx, AlgebraicIndependent, this]; simp
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
sumElim_iff
null
iff_adjoin_image (s : Set ι) : AlgebraicIndependent R x ↔ AlgebraicIndependent R (fun i : s ↦ x i) ∧ AlgebraicIndepOn (adjoin R (x '' s)) x sᶜ := by rw [show x '' s = range fun i : s ↦ x i by ext; simp] convert ← sumElim_iff classical apply algebraicIndependent_equiv' ((Equiv.sumComm ..).trans (Equiv.Set.sumCompl ..)) ext (_ | _) <;> rfl
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
iff_adjoin_image
null
iff_adjoin_image_compl (s : Set ι) : AlgebraicIndependent R x ↔ AlgebraicIndependent R (fun i : ↥sᶜ ↦ x i) ∧ AlgebraicIndepOn (adjoin R (x '' sᶜ)) x s := by convert ← iff_adjoin_image _; apply compl_compl
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
iff_adjoin_image_compl
null
iff_transcendental_adjoin_image (i : ι) : AlgebraicIndependent R x ↔ AlgebraicIndependent R (fun j : {j // j ≠ i} ↦ x j) ∧ Transcendental (adjoin R (x '' {i}ᶜ)) (x i) := (iff_adjoin_image_compl _).trans <| and_congr_right fun _ ↦ algebraicIndependent_unique_type_iff (ι := {j // j = i}) variable (hx : AlgebraicIndependent R x) include hx
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
iff_transcendental_adjoin_image
null
sumElim {ι'} {y : ι' → A} (hy : AlgebraicIndependent (adjoin R (range x)) y) : AlgebraicIndependent R (Sum.elim y x) := sumElim_iff.mpr ⟨hx, hy⟩
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
sumElim
null
sumElim_of_tower {ι'} {y : ι' → A} (hxS : range x ⊆ range (algebraMap S A)) (hy : AlgebraicIndependent S y) : AlgebraicIndependent R (Sum.elim y x) := by let e := AlgEquiv.ofInjective (IsScalarTower.toAlgHom R S A) hy.algebraMap_injective set Rx := adjoin R (range x) let _ : Algebra Rx S := (e.symm.toAlgHom.comp <| Subalgebra.inclusion <| adjoin_le hxS).toAlgebra have : IsScalarTower Rx S A := .of_algebraMap_eq fun x ↦ show _ = (e (e.symm _)).1 by simp; rfl refine hx.sumElim (hy.restrictScalars (e.symm.injective.comp ?_)) simpa only [AlgHom.coe_toRingHom] using Subalgebra.inclusion_injective _ omit hx in
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
sumElim_of_tower
null
sumElim_comp {ι'} {x : ι → S} {y : ι' → A} (hx : AlgebraicIndependent R x) (hy : AlgebraicIndependent S y) : AlgebraicIndependent R (Sum.elim y (algebraMap S A ∘ x)) := (hx.map' (f := IsScalarTower.toAlgHom R S A) hy.algebraMap_injective).sumElim_of_tower (range_comp_subset_range ..) hy
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
sumElim_comp
null
adjoin_of_disjoint {s t : Set ι} (h : Disjoint s t) : AlgebraicIndependent (adjoin R (x '' s)) fun i : t ↦ x i := ((iff_adjoin_image s).mp hx).2.comp (inclusion _) (inclusion_injective h.subset_compl_left)
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
adjoin_of_disjoint
null
adjoin_iff_disjoint [Nontrivial A] {s t : Set ι} : (AlgebraicIndependent (adjoin R (x '' s)) fun i : t ↦ x i) ↔ Disjoint s t := by refine ⟨fun ind ↦ of_not_not fun ndisj ↦ ?_, adjoin_of_disjoint hx⟩ have ⟨i, hs, ht⟩ := Set.not_disjoint_iff.mp ndisj refine ind.transcendental ⟨i, ht⟩ (isAlgebraic_algebraMap (⟨_, subset_adjoin ?_⟩ : adjoin R _)) exact ⟨i, hs, rfl⟩
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
adjoin_iff_disjoint
null
transcendental_adjoin {s : Set ι} {i : ι} (hi : i ∉ s) : Transcendental (adjoin R (x '' s)) (x i) := by convert ← hx.adjoin_of_disjoint (Set.disjoint_singleton_right.mpr hi) rw [algebraicIndependent_singleton_iff ⟨i, rfl⟩]
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
transcendental_adjoin
null
transcendental_adjoin_iff [Nontrivial A] {s : Set ι} {i : ι} : Transcendental (adjoin R (x '' s)) (x i) ↔ i ∉ s := by rw [← Set.disjoint_singleton_right] convert ← hx.adjoin_iff_disjoint (t := {i}) rw [algebraicIndependent_singleton_iff ⟨i, rfl⟩]
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
transcendental_adjoin_iff
null
lift_trdeg_add_le [Nontrivial R] [FaithfulSMul R S] [FaithfulSMul S A] : lift.{v} (trdeg R S) + lift.{u} (trdeg S A) ≤ lift.{u} (trdeg R A) := by simp_rw [trdeg, lift_iSup (bddAbove_range _)] simp_rw [Cardinal.ciSup_add_ciSup _ (bddAbove_range _) _ (bddAbove_range _), add_comm (lift.{v, u} _), ← mk_sum] refine ciSup_le fun ⟨s, hs⟩ ↦ ciSup_le fun ⟨t, ht⟩ ↦ ?_ have := hs.sumElim_comp ht refine le_ciSup_of_le (bddAbove_range _) ⟨_, this.to_subtype_range⟩ ?_ rw [← lift_umax, mk_range_eq_of_injective this.injective, lift_id']
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
lift_trdeg_add_le
null
trdeg_add_le [Nontrivial R] {A : Type u} [CommRing A] [Algebra R A] [Algebra S A] [FaithfulSMul R S] [FaithfulSMul S A] [IsScalarTower R S A] : trdeg R S + trdeg S A ≤ trdeg R A := by rw [← (trdeg R S).lift_id, ← (trdeg S A).lift_id, ← (trdeg R A).lift_id] exact lift_trdeg_add_le
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
trdeg_add_le
null
MvPolynomial.algebraicIndependent_polynomial_aeval_X (f : ι → Polynomial R) (hf : ∀ i, Transcendental R (f i)) : AlgebraicIndependent R fun i ↦ Polynomial.aeval (X i : MvPolynomial ι R) (f i) := by set x := fun i ↦ Polynomial.aeval (X i : MvPolynomial ι R) (f i) refine algebraicIndependent_of_finite_type' (C_injective _ _) fun t _ _ i hi ↦ ?_ have hle : adjoin R (x '' t) ≤ supported R t := by rw [Algebra.adjoin_le_iff, Set.image_subset_iff] intro _ h rw [Set.mem_preimage] refine Algebra.adjoin_mono ?_ (Polynomial.aeval_mem_adjoin_singleton R _) simp_rw [singleton_subset_iff, Set.mem_image_of_mem _ h] exact (transcendental_supported_polynomial_aeval_X R hi (hf i)).of_tower_top_of_subalgebra_le hle
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
MvPolynomial.algebraicIndependent_polynomial_aeval_X
If for each `i : ι`, `f_i : R[X]` is transcendental over `R`, then `{f_i(X_i) | i : ι}` in `MvPolynomial ι R` is algebraically independent over `R`.
AlgebraicIndependent.polynomial_aeval_of_transcendental (hx : AlgebraicIndependent R x) {f : ι → Polynomial R} (hf : ∀ i, Transcendental R (f i)) : AlgebraicIndependent R fun i ↦ Polynomial.aeval (x i) (f i) := by convert aeval_of_algebraicIndependent hx (algebraicIndependent_polynomial_aeval_X _ hf) rw [← AlgHom.comp_apply] congr 1; ext1; simp
theorem
RingTheory
[ "Mathlib.Data.Fin.Tuple.Reflection", "Mathlib.RingTheory.Algebraic.MvPolynomial", "Mathlib.RingTheory.AlgebraicIndependent.Basic" ]
Mathlib/RingTheory/AlgebraicIndependent/Transcendental.lean
AlgebraicIndependent.polynomial_aeval_of_transcendental
If `{x_i : A | i : ι}` is algebraically independent over `R`, and for each `i`, `f_i : R[X]` is transcendental over `R`, then `{f_i(x_i) | i : ι}` is also algebraically independent over `R`.
isUnit_of_isIntegral_of_nonZeroDivisor {a : A} (hi : IsIntegral R a) (ha : a ∈ A⁰) : IsUnit a := let B := Algebra.adjoin R {a} let b : B := ⟨a, Algebra.self_mem_adjoin_singleton R a⟩ haveI : Module.Finite R B := Algebra.finite_adjoin_simple_of_isIntegral hi haveI : IsArtinianRing B := isArtinian_of_tower R inferInstance have hinj : Function.Injective B.subtype := Subtype.val_injective have hb : b ∈ B⁰ := comap_nonZeroDivisors_le_of_injective hinj ha (isUnit_of_mem_nonZeroDivisors hb).map B.subtype
theorem
RingTheory
[ "Mathlib.RingTheory.Artinian.Module", "Mathlib.RingTheory.IntegralClosure.Algebra.Defs", "Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic" ]
Mathlib/RingTheory/Artinian/Algebra.lean
isUnit_of_isIntegral_of_nonZeroDivisor
In an `R`-algebra over an Artinian ring `R`, if an element is integral and is not a zero divisor, then it is a unit.
isUnit_iff_nonZeroDivisor_of_isIntegral {a : A} (hi : IsIntegral R a) : IsUnit a ↔ a ∈ A⁰ := ⟨IsUnit.mem_nonZeroDivisors, isUnit_of_isIntegral_of_nonZeroDivisor hi⟩
theorem
RingTheory
[ "Mathlib.RingTheory.Artinian.Module", "Mathlib.RingTheory.IntegralClosure.Algebra.Defs", "Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic" ]
Mathlib/RingTheory/Artinian/Algebra.lean
isUnit_iff_nonZeroDivisor_of_isIntegral
Integral element of an algebra over Artinian ring `R` is either a zero divisor or a unit.
isUnit_of_nonZeroDivisor_of_isIntegral' [Algebra.IsIntegral R A] {a : A} (ha : a ∈ A⁰) : IsUnit a := isUnit_of_isIntegral_of_nonZeroDivisor (R := R) (Algebra.IsIntegral.isIntegral a) ha
theorem
RingTheory
[ "Mathlib.RingTheory.Artinian.Module", "Mathlib.RingTheory.IntegralClosure.Algebra.Defs", "Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic" ]
Mathlib/RingTheory/Artinian/Algebra.lean
isUnit_of_nonZeroDivisor_of_isIntegral'
In an `R`-algebra over an Artinian ring `R`, if an element is integral and is not a zero divisor, then it is a unit.
isUnit_iff_nonZeroDivisor_of_isIntegral' [Algebra.IsIntegral R A] {a : A} : IsUnit a ↔ a ∈ A⁰ := isUnit_iff_nonZeroDivisor_of_isIntegral (R := R) (Algebra.IsIntegral.isIntegral a)
theorem
RingTheory
[ "Mathlib.RingTheory.Artinian.Module", "Mathlib.RingTheory.IntegralClosure.Algebra.Defs", "Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic" ]
Mathlib/RingTheory/Artinian/Algebra.lean
isUnit_iff_nonZeroDivisor_of_isIntegral'
Integral element of an algebra over Artinian ring `R` is either a zero divisor or a unit.
isUnit_submonoid_eq_of_isIntegral [Algebra.IsIntegral R A] : IsUnit.submonoid A = A⁰ := by ext; simpa [IsUnit.mem_submonoid_iff] using isUnit_iff_nonZeroDivisor_of_isIntegral' (R := R)
theorem
RingTheory
[ "Mathlib.RingTheory.Artinian.Module", "Mathlib.RingTheory.IntegralClosure.Algebra.Defs", "Mathlib.RingTheory.IntegralClosure.IsIntegral.Basic" ]
Mathlib/RingTheory/Artinian/Algebra.lean
isUnit_submonoid_eq_of_isIntegral
null
IsArtinian (R M) [Semiring R] [AddCommMonoid M] [Module R M] : Prop := WellFoundedLT (Submodule R M)
abbrev
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinian
`IsArtinian R M` is the proposition that `M` is an Artinian `R`-module, implemented as the well-foundedness of submodule inclusion.
isArtinian_iff (R M) [Semiring R] [AddCommMonoid M] [Module R M] : IsArtinian R M ↔ WellFounded (· < · : Submodule R M → Submodule R M → Prop) := isWellFounded_iff _ _
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_iff
null
LinearMap.isArtinian_iff_of_bijective {S P} [Semiring S] [AddCommMonoid P] [Module S P] {σ : R →+* S} [RingHomSurjective σ] (l : M →ₛₗ[σ] P) (hl : Function.Bijective l) : IsArtinian R M ↔ IsArtinian S P := let e := Submodule.orderIsoMapComapOfBijective l hl ⟨fun _ ↦ e.symm.strictMono.wellFoundedLT, fun _ ↦ e.strictMono.wellFoundedLT⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
LinearMap.isArtinian_iff_of_bijective
null
isArtinian_of_injective (f : M →ₗ[R] P) (h : Function.Injective f) [IsArtinian R P] : IsArtinian R M := ⟨Subrelation.wf (fun {A B} hAB => show A.map f < B.map f from Submodule.map_strictMono_of_injective h hAB) (InvImage.wf (Submodule.map f) IsWellFounded.wf)⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_injective
null
isArtinian_submodule' [IsArtinian R M] (N : Submodule R M) : IsArtinian R N := isArtinian_of_injective N.subtype Subtype.val_injective
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_submodule'
null
isArtinian_of_le {s t : Submodule R M} [IsArtinian R t] (h : s ≤ t) : IsArtinian R s := isArtinian_of_injective (Submodule.inclusion h) (Submodule.inclusion_injective h) variable (M) in
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_le
null
isArtinian_of_surjective (f : M →ₗ[R] P) (hf : Function.Surjective f) [IsArtinian R M] : IsArtinian R P := ⟨Subrelation.wf (fun {A B} hAB => show A.comap f < B.comap f from Submodule.comap_strictMono_of_surjective hf hAB) (InvImage.wf (Submodule.comap f) IsWellFounded.wf)⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_surjective
null
isArtinian_of_surjective_algebraMap {S : Type*} [CommSemiring S] [Algebra S R] [Module S M] [IsArtinian R M] [IsScalarTower S R M] (H : Function.Surjective (algebraMap S R)) : IsArtinian S M := by apply (OrderEmbedding.wellFoundedLT (β := Submodule R M)) refine ⟨⟨?_, ?_⟩, ?_⟩ · intro N refine {toAddSubmonoid := N.toAddSubmonoid, smul_mem' := ?_} intro c x hx obtain ⟨r, rfl⟩ := H c suffices r • x ∈ N by simpa [Algebra.algebraMap_eq_smul_one, smul_assoc] apply N.smul_mem _ hx · intro N1 N2 h rwa [Submodule.ext_iff] at h ⊢ · intro N1 N2 rfl
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_surjective_algebraMap
If `M` is an Artinian `R` module, and `S` is an `R`-algebra with a surjective algebra map, then `M` is an Artinian `S` module.
isArtinian_range (f : M →ₗ[R] P) [IsArtinian R M] : IsArtinian R (LinearMap.range f) := isArtinian_of_surjective _ _ f.surjective_rangeRestrict
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_range
null
isArtinian_of_linearEquiv (f : M ≃ₗ[R] P) [IsArtinian R M] : IsArtinian R P := isArtinian_of_surjective _ f.toLinearMap f.toEquiv.surjective
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_linearEquiv
null
LinearEquiv.isArtinian_iff (f : M ≃ₗ[R] P) : IsArtinian R M ↔ IsArtinian R P := ⟨fun _ ↦ isArtinian_of_linearEquiv f, fun _ ↦ isArtinian_of_linearEquiv f.symm⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
LinearEquiv.isArtinian_iff
null
isArtinian_of_finite [Finite M] : IsArtinian R M := ⟨Finite.wellFounded_of_trans_of_irrefl _⟩ open Submodule
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_finite
null
IsArtinian.finite_of_linearIndependent [Nontrivial R] [h : IsArtinian R M] {s : Set M} (hs : LinearIndependent R ((↑) : s → M)) : s.Finite := by refine by_contradiction fun hf ↦ (RelEmbedding.wellFounded_iff_isEmpty.1 h.wf).elim' ?_ have f : ℕ ↪ s := Set.Infinite.natEmbedding s hf have : ∀ n, (↑) ∘ f '' { m | n ≤ m } ⊆ s := by rintro n x ⟨y, _, rfl⟩ exact (f y).2 have : ∀ a b : ℕ, a ≤ b ↔ span R (Subtype.val ∘ f '' { m | b ≤ m }) ≤ span R (Subtype.val ∘ f '' { m | a ≤ m }) := by intro a b rw [span_le_span_iff hs (this b) (this a), Set.image_subset_image_iff (Subtype.coe_injective.comp f.injective), Set.subset_def] simp only [Set.mem_setOf_eq] exact ⟨fun hab x ↦ hab.trans, (· _ le_rfl)⟩ exact ⟨⟨fun n ↦ span R (Subtype.val ∘ f '' { m | n ≤ m }), fun x y ↦ by rw [le_antisymm_iff, ← this y x, ← this x y] exact fun ⟨h₁, h₂⟩ ↦ le_antisymm_iff.2 ⟨h₂, h₁⟩⟩, by intro a b conv_rhs => rw [GT.gt, lt_iff_le_not_ge, this, this, ← lt_iff_le_not_ge] rfl⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinian.finite_of_linearIndependent
null
set_has_minimal_iff_artinian : (∀ a : Set <| Submodule R M, a.Nonempty → ∃ M' ∈ a, ∀ I ∈ a, ¬I < M') ↔ IsArtinian R M := by rw [isArtinian_iff, WellFounded.wellFounded_iff_has_min]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
set_has_minimal_iff_artinian
A module is Artinian iff every nonempty set of submodules has a minimal submodule among them.
IsArtinian.set_has_minimal [IsArtinian R M] (a : Set <| Submodule R M) (ha : a.Nonempty) : ∃ M' ∈ a, ∀ I ∈ a, ¬I < M' := set_has_minimal_iff_artinian.mpr ‹_› a ha
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinian.set_has_minimal
null
monotone_stabilizes_iff_artinian : (∀ f : ℕ →o (Submodule R M)ᵒᵈ, ∃ n, ∀ m, n ≤ m → f n = f m) ↔ IsArtinian R M := wellFoundedGT_iff_monotone_chain_condition.symm
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
monotone_stabilizes_iff_artinian
A module is Artinian iff every decreasing chain of submodules stabilizes.
monotone_stabilizes (f : ℕ →o (Submodule R M)ᵒᵈ) : ∃ n, ∀ m, n ≤ m → f n = f m := monotone_stabilizes_iff_artinian.mpr ‹_› f
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
monotone_stabilizes
null
eventuallyConst_of_isArtinian (f : ℕ →o (Submodule R M)ᵒᵈ) : atTop.EventuallyConst f := by simp_rw [eventuallyConst_atTop, eq_comm] exact monotone_stabilizes f
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
eventuallyConst_of_isArtinian
null
induction {P : Submodule R M → Prop} (hgt : ∀ I, (∀ J < I, P J) → P I) (I : Submodule R M) : P I := WellFoundedLT.induction I hgt open Function
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
induction
If `∀ I > J, P I` implies `P J`, then `P` holds for all submodules.
surjective_of_injective_endomorphism (f : M →ₗ[R] M) (s : Injective f) : Surjective f := by have h := ‹IsArtinian R M›; contrapose! h rw [IsArtinian, WellFoundedLT, isWellFounded_iff] refine (RelEmbedding.natGT (LinearMap.range <| f ^ ·) ?_).not_wellFounded intro n simp_rw [pow_succ, Module.End.mul_eq_comp, LinearMap.range_comp, ← Submodule.map_top (f ^ n)] refine Submodule.map_strictMono_of_injective (Module.End.iterate_injective s n) (Ne.lt_top ?_) rwa [Ne, LinearMap.range_eq_top]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
surjective_of_injective_endomorphism
Any injective endomorphism of an Artinian module is surjective.
bijective_of_injective_endomorphism (f : M →ₗ[R] M) (s : Injective f) : Bijective f := ⟨s, surjective_of_injective_endomorphism f s⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
bijective_of_injective_endomorphism
Any injective endomorphism of an Artinian module is bijective.
disjoint_partial_infs_eventually_top (f : ℕ → Submodule R M) (h : ∀ n, Disjoint (partialSups (OrderDual.toDual ∘ f) n) (OrderDual.toDual (f (n + 1)))) : ∃ n : ℕ, ∀ m, n ≤ m → f m = ⊤ := by rsuffices ⟨n, w⟩ : ∃ n : ℕ, ∀ m, n ≤ m → OrderDual.toDual f (m + 1) = ⊤ · use n + 1 rintro (_ | m) p · cases p · apply w exact Nat.succ_le_succ_iff.mp p obtain ⟨n, w⟩ := monotone_stabilizes (partialSups (OrderDual.toDual ∘ f)) refine ⟨n, fun m p ↦ (h m).eq_bot_of_ge <| sup_eq_left.mp ?_⟩ simpa only [partialSups_add_one] using (w (m + 1) <| le_add_right p).symm.trans <| w m p
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
disjoint_partial_infs_eventually_top
A sequence `f` of submodules of an Artinian module, with the supremum `f (n+1)` and the infimum of `f 0`, ..., `f n` being ⊤, is eventually ⊤.
eventually_iInf_range_pow_eq (f : Module.End R M) : ∀ᶠ n in atTop, ⨅ m, LinearMap.range (f ^ m) = LinearMap.range (f ^ n) := by obtain ⟨n, hn : ∀ m, n ≤ m → LinearMap.range (f ^ n) = LinearMap.range (f ^ m)⟩ := IsArtinian.monotone_stabilizes f.iterateRange refine eventually_atTop.mpr ⟨n, fun l hl ↦ le_antisymm (iInf_le _ _) (le_iInf fun m ↦ ?_)⟩ rcases le_or_gt l m with h | h · rw [← hn _ (hl.trans h), hn _ hl] · exact f.iterateRange.monotone h.le
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
eventually_iInf_range_pow_eq
null
isArtinian_of_quotient_of_artinian (N : Submodule R M) [IsArtinian R M] : IsArtinian R (M ⧸ N) := isArtinian_of_surjective M (Submodule.mkQ N) (Submodule.Quotient.mk_surjective N)
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_quotient_of_artinian
null
isArtinian_of_range_eq_ker [IsArtinian R M] [IsArtinian R P] (f : M →ₗ[R] N) (g : N →ₗ[R] P) (h : LinearMap.range f = LinearMap.ker g) : IsArtinian R N := wellFounded_lt_exact_sequence (LinearMap.range f) (Submodule.map ((LinearMap.ker f).liftQ f le_rfl)) (Submodule.comap ((LinearMap.ker f).liftQ f le_rfl)) (Submodule.comap g.rangeRestrict) (Submodule.map g.rangeRestrict) (Submodule.gciMapComap <| LinearMap.ker_eq_bot.mp <| Submodule.ker_liftQ_eq_bot _ _ _ le_rfl) (Submodule.giMapComap g.surjective_rangeRestrict) (by simp [Submodule.map_comap_eq, inf_comm, Submodule.range_liftQ]) (by simp [Submodule.comap_map_eq, h])
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_range_eq_ker
null
isArtinian_iff_submodule_quotient (S : Submodule R P) : IsArtinian R P ↔ IsArtinian R S ∧ IsArtinian R (P ⧸ S) := by refine ⟨fun h ↦ ⟨inferInstance, inferInstance⟩, fun ⟨_, _⟩ ↦ ?_⟩ apply isArtinian_of_range_eq_ker S.subtype S.mkQ rw [Submodule.ker_mkQ, Submodule.range_subtype]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_iff_submodule_quotient
null
isArtinian_prod [IsArtinian R M] [IsArtinian R P] : IsArtinian R (M × P) := isArtinian_of_range_eq_ker (LinearMap.inl R M P) (LinearMap.snd R M P) (LinearMap.range_inl R M P)
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_prod
null
isArtinian_sup (M₁ M₂ : Submodule R P) [IsArtinian R M₁] [IsArtinian R M₂] : IsArtinian R ↥(M₁ ⊔ M₂) := by have := isArtinian_range (M₁.subtype.coprod M₂.subtype) rwa [LinearMap.range_coprod, Submodule.range_subtype, Submodule.range_subtype] at this variable {ι : Type*} [Finite ι]
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_sup
null
isArtinian_pi : ∀ {M : ι → Type*} [Π i, AddCommGroup (M i)] [Π i, Module R (M i)] [∀ i, IsArtinian R (M i)], IsArtinian R (Π i, M i) := by apply Finite.induction_empty_option _ _ _ ι · exact fun e h ↦ isArtinian_of_linearEquiv (LinearEquiv.piCongrLeft R _ e) · infer_instance · exact fun ih ↦ isArtinian_of_linearEquiv (LinearEquiv.piOptionEquivProd R).symm
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_pi
null
isArtinian_pi' [IsArtinian R M] : IsArtinian R (ι → M) := isArtinian_pi
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_pi'
A version of `isArtinian_pi` for non-dependent functions. We need this instance because sometimes Lean fails to apply the dependent version in non-dependent settings (e.g., it fails to prove that `ι → ℝ` is finite dimensional over `ℝ`).
isArtinian_finsupp [IsArtinian R M] : IsArtinian R (ι →₀ M) := isArtinian_of_linearEquiv (Finsupp.linearEquivFunOnFinite _ _ _).symm
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_finsupp
null
isArtinian_iSup : ∀ {M : ι → Submodule R P} [∀ i, IsArtinian R (M i)], IsArtinian R ↥(⨆ i, M i) := by apply Finite.induction_empty_option _ _ _ ι · intro _ _ e h _ _; rw [← e.iSup_comp]; apply h · intros; rw [iSup_of_empty]; infer_instance · intro _ _ ih _ _; rw [iSup_option]; infer_instance variable (R M) in
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_iSup
null
IsArtinian.isSemisimpleModule_iff_jacobson [IsArtinian R M] : IsSemisimpleModule R M ↔ Module.jacobson R M = ⊥ := ⟨fun _ ↦ IsSemisimpleModule.jacobson_eq_bot R M, fun h ↦ have ⟨s, hs⟩ := Finset.exists_inf_le (Subtype.val (p := fun m : Submodule R M ↦ IsCoatom m)) have _ (m : s) : IsSimpleModule R (M ⧸ m.1.1) := isSimpleModule_iff_isCoatom.mpr m.1.2 let f : M →ₗ[R] ∀ m : s, M ⧸ m.1.1 := LinearMap.pi fun m ↦ m.1.1.mkQ .of_injective f <| LinearMap.ker_eq_bot.mp <| le_bot_iff.mp fun x hx ↦ by rw [← h, Module.jacobson, Submodule.mem_sInf] exact fun m hm ↦ hs ⟨m, hm⟩ <| Submodule.mem_finsetInf.mpr fun i hi ↦ (Submodule.Quotient.mk_eq_zero i.1).mp <| congr_fun hx ⟨i, hi⟩⟩ open Submodule Function
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinian.isSemisimpleModule_iff_jacobson
null
eventually_codisjoint_ker_pow_range_pow (f : Module.End R M) : ∀ᶠ n in atTop, Codisjoint (LinearMap.ker (f ^ n)) (LinearMap.range (f ^ n)) := by obtain ⟨n, hn : ∀ m, n ≤ m → LinearMap.range (f ^ n) = LinearMap.range (f ^ m)⟩ := IsArtinian.monotone_stabilizes f.iterateRange refine eventually_atTop.mpr ⟨n, fun m hm ↦ codisjoint_iff.mpr ?_⟩ simp_rw [← hn _ hm, Submodule.eq_top_iff', Submodule.mem_sup] intro x rsuffices ⟨y, hy⟩ : ∃ y, (f ^ m) ((f ^ n) y) = (f ^ m) x · exact ⟨x - (f ^ n) y, by simp [hy], (f ^ n) y, by simp⟩ simp_rw [f.pow_apply n, f.pow_apply m, ← iterate_add_apply, ← f.pow_apply (m + n), ← f.pow_apply m, ← mem_range (f := _), ← hn _ (n.le_add_left m), hn _ hm] exact LinearMap.mem_range_self (f ^ m) x
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
eventually_codisjoint_ker_pow_range_pow
For any endomorphism of an Artinian module, any sufficiently high iterate has codisjoint kernel and range.
eventually_isCompl_ker_pow_range_pow [IsNoetherian R M] (f : Module.End R M) : ∀ᶠ n in atTop, IsCompl (LinearMap.ker (f ^ n)) (LinearMap.range (f ^ n)) := by filter_upwards [f.eventually_disjoint_ker_pow_range_pow.and f.eventually_codisjoint_ker_pow_range_pow] with n hn simpa only [isCompl_iff]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
eventually_isCompl_ker_pow_range_pow
This is the Fitting decomposition of the module `M` with respect to the endomorphism `f`. See also `LinearMap.isCompl_iSup_ker_pow_iInf_range_pow` for an alternative spelling.
isCompl_iSup_ker_pow_iInf_range_pow [IsNoetherian R M] (f : M →ₗ[R] M) : IsCompl (⨆ n, LinearMap.ker (f ^ n)) (⨅ n, LinearMap.range (f ^ n)) := by obtain ⟨k, hk⟩ := eventually_atTop.mp <| f.eventually_isCompl_ker_pow_range_pow.and <| f.eventually_iInf_range_pow_eq.and f.eventually_iSup_ker_pow_eq obtain ⟨h₁, h₂, h₃⟩ := hk k (le_refl k) rwa [h₂, h₃]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isCompl_iSup_ker_pow_iInf_range_pow
This is the Fitting decomposition of the module `M` with respect to the endomorphism `f`. See also `LinearMap.eventually_isCompl_ker_pow_range_pow` for an alternative spelling.
range_smul_pow_stabilizes (r : R) : ∃ n : ℕ, ∀ m, n ≤ m → LinearMap.range (r ^ n • LinearMap.id : M →ₗ[R] M) = LinearMap.range (r ^ m • LinearMap.id : M →ₗ[R] M) := monotone_stabilizes ⟨fun n => LinearMap.range (r ^ n • LinearMap.id : M →ₗ[R] M), fun n m h x ⟨y, hy⟩ => ⟨r ^ (m - n) • y, by dsimp at hy ⊢ rw [← smul_assoc, smul_eq_mul, ← pow_add, ← hy, add_tsub_cancel_of_le h]⟩⟩ variable {M}
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
range_smul_pow_stabilizes
null
exists_pow_succ_smul_dvd (r : R) (x : M) : ∃ (n : ℕ) (y : M), r ^ n.succ • y = r ^ n • x := by obtain ⟨n, hn⟩ := IsArtinian.range_smul_pow_stabilizes M r simp_rw [SetLike.ext_iff] at hn exact ⟨n, by simpa using hn n.succ n.le_succ (r ^ n • x)⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
exists_pow_succ_smul_dvd
null
isArtinian_of_submodule_of_artinian (R M) [Semiring R] [AddCommMonoid M] [Module R M] (N : Submodule R M) (_ : IsArtinian R M) : IsArtinian R N := inferInstance
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_submodule_of_artinian
null
isArtinian_of_tower (R) {S M} [Semiring R] [Semiring S] [AddCommMonoid M] [SMul R S] [Module S M] [Module R M] [IsScalarTower R S M] (h : IsArtinian R M) : IsArtinian S M := ⟨(Submodule.restrictScalarsEmbedding R S M).wellFounded h.wf⟩ assert_not_exists IsLocalization IsLocalRing
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_tower
If `M / S / R` is a scalar tower, and `M / R` is Artinian, then `M / S` is also Artinian.
@[stacks 00J5] IsArtinianRing (R) [Semiring R] := IsArtinian R R
abbrev
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinianRing
A ring is Artinian if it is Artinian as a module over itself. Strictly speaking, this should be called `IsLeftArtinianRing` but we omit the `Left` for convenience in the commutative case. For a right Artinian ring, use `IsArtinian Rᵐᵒᵖ R`. For equivalent definitions, see `Mathlib/RingTheory/Artinian/Ring.lean`.
isArtinianRing_iff {R} [Semiring R] : IsArtinianRing R ↔ IsArtinian R R := Iff.rfl
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinianRing_iff
null
DivisionSemiring.instIsArtinianRing {K : Type*} [DivisionSemiring K] : IsArtinianRing K := ⟨Finite.wellFounded_of_trans_of_irrefl _⟩
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
DivisionSemiring.instIsArtinianRing
null
DivisionRing.instIsArtinianRing {K : Type*} [DivisionRing K] : IsArtinianRing K := inferInstance
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
DivisionRing.instIsArtinianRing
null
Ring.isArtinian_of_zero_eq_one {R} [Semiring R] (h01 : (0 : R) = 1) : IsArtinianRing R := have := subsingleton_of_zero_eq_one h01 inferInstance
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
Ring.isArtinian_of_zero_eq_one
null
isArtinian_of_fg_of_artinian' {R M} [Ring R] [AddCommGroup M] [Module R M] [IsArtinianRing R] [Module.Finite R M] : IsArtinian R M := have ⟨_, _, h⟩ := Module.Finite.exists_fin' R M isArtinian_of_surjective _ _ h
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_fg_of_artinian'
null
isArtinian_of_fg_of_artinian {R M} [Ring R] [AddCommGroup M] [Module R M] (N : Submodule R M) [IsArtinianRing R] (hN : N.FG) : IsArtinian R N := by rw [← Module.Finite.iff_fg] at hN; infer_instance
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_of_fg_of_artinian
null
IsArtinianRing.of_finite (R S) [Ring R] [Ring S] [Module R S] [IsScalarTower R S S] [IsArtinianRing R] [Module.Finite R S] : IsArtinianRing S := isArtinian_of_tower R isArtinian_of_fg_of_artinian'
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
IsArtinianRing.of_finite
null
isArtinian_span_of_finite (R) {M} [Ring R] [AddCommGroup M] [Module R M] [IsArtinianRing R] {A : Set M} (hA : A.Finite) : IsArtinian R (Submodule.span R A) := isArtinian_of_fg_of_artinian _ (Submodule.fg_def.mpr ⟨A, hA, rfl⟩)
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinian_span_of_finite
In a module over an Artinian ring, the submodule generated by finitely many vectors is Artinian.
Function.Surjective.isArtinianRing {R} [Semiring R] {S} [Semiring S] {F} [FunLike F R S] [RingHomClass F R S] {f : F} (hf : Function.Surjective f) [H : IsArtinianRing R] : IsArtinianRing S := by rw [isArtinianRing_iff] at H ⊢ exact ⟨(Ideal.orderEmbeddingOfSurjective f hf).wellFounded H.wf⟩
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
Function.Surjective.isArtinianRing
null
isArtinianRing_rangeS {R} [Semiring R] {S} [Semiring S] (f : R →+* S) [IsArtinianRing R] : IsArtinianRing f.rangeS := f.rangeSRestrict_surjective.isArtinianRing
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinianRing_rangeS
null
isArtinianRing_range {R} [Ring R] {S} [Ring S] (f : R →+* S) [IsArtinianRing R] : IsArtinianRing f.range := isArtinianRing_rangeS f
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isArtinianRing_range
null
RingEquiv.isArtinianRing {R S} [Semiring R] [Semiring S] (f : R ≃+* S) [IsArtinianRing R] : IsArtinianRing S := f.surjective.isArtinianRing
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
RingEquiv.isArtinianRing
null
isUnit_iff_isRightRegular [IsArtinianRing R] {x : R} : IsUnit x ↔ IsRightRegular x := by rw [IsRightRegular, IsUnit.isUnit_iff_mulRight_bijective, Bijective, and_iff_left_of_imp] exact IsArtinian.surjective_of_injective_endomorphism (.toSpanSingleton R R x)
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_isRightRegular
null
isUnit_iff_isRegular [IsArtinianRing R] {x : R} : IsUnit x ↔ IsRegular x := by rw [isRegular_iff, ← isUnit_iff_isRightRegular, and_iff_right_of_imp (·.isRegular.1)]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_isRegular
null
isUnit_iff_isLeftRegular [IsArtinianRing Rᵐᵒᵖ] {x : R} : IsUnit x ↔ IsLeftRegular x := by rw [← isRightRegular_op, ← isUnit_op, isUnit_iff_isRightRegular]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_isLeftRegular
null
isUnit_iff_isRegular_of_mulOpposite [IsArtinianRing Rᵐᵒᵖ] {x : R} : IsUnit x ↔ IsRegular x := by rw [isRegular_iff, ← isUnit_iff_isLeftRegular, and_iff_left_of_imp (·.isRegular.2)]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_isRegular_of_mulOpposite
null
isUnit_of_mem_nonZeroDivisors [IsArtinianRing R] {a : R} (ha : a ∈ R⁰) : IsUnit a := by rwa [isUnit_iff_isRegular, isRegular_iff_mem_nonZeroDivisors]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_of_mem_nonZeroDivisors
If an element of an Artinian ring is not a zero divisor then it is a unit.
isUnit_of_mem_nonZeroDivisors_of_mulOpposite [IsArtinianRing Rᵐᵒᵖ] {a : R} (ha : a ∈ R⁰) : IsUnit a := by rwa [isUnit_iff_isRegular_of_mulOpposite, isRegular_iff_mem_nonZeroDivisors]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_of_mem_nonZeroDivisors_of_mulOpposite
null
isUnit_iff_mem_nonZeroDivisors [IsArtinianRing R] {a : R} : IsUnit a ↔ a ∈ R⁰ := by rw [isUnit_iff_isRegular, isRegular_iff_mem_nonZeroDivisors]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_mem_nonZeroDivisors
In an Artinian ring, an element is a unit iff it is a non-zero-divisor. See also `isUnit_iff_mem_nonZeroDivisors_of_finite`.
isUnit_iff_mem_nonZeroDivisors_of_mulOpposite [IsArtinianRing Rᵐᵒᵖ] {a : R} : IsUnit a ↔ a ∈ R⁰ := by rw [isUnit_iff_isRegular_of_mulOpposite, isRegular_iff_mem_nonZeroDivisors] variable (R)
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnit_iff_mem_nonZeroDivisors_of_mulOpposite
null
isUnitSubmonoid_eq [IsArtinianRing R] : IsUnit.submonoid R = R⁰ := by ext; simp [IsUnit.mem_submonoid_iff, isUnit_iff_mem_nonZeroDivisors] @[deprecated (since := "2025-08-26")] alias isUnit_submonoid_eq := isUnitSubmonoid_eq
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnitSubmonoid_eq
null
isUnitSubmonoid_eq_of_mulOpposite [IsArtinianRing Rᵐᵒᵖ] : IsUnit.submonoid R = R⁰ := by ext; simp [IsUnit.mem_submonoid_iff, isUnit_iff_mem_nonZeroDivisors_of_mulOpposite]
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnitSubmonoid_eq_of_mulOpposite
null
isUnitSubmonoid_eq_nonZeroDivisorsRight [IsArtinianRing R] : IsUnit.submonoid R = nonZeroDivisorsRight R := by ext; rw [← isRightRegular_iff_mem_nonZeroDivisorsRight]; exact isUnit_iff_isRightRegular
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isUnitSubmonoid_eq_nonZeroDivisorsRight
null
nonZeroDivisorsLeft_eq_isUnitSubmonoid [IsArtinianRing Rᵐᵒᵖ] : IsUnit.submonoid R = nonZeroDivisorsLeft R := by ext; rw [← isLeftRegular_iff_mem_nonZeroDivisorsLeft]; exact isUnit_iff_isLeftRegular
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
nonZeroDivisorsLeft_eq_isUnitSubmonoid
null
@[stacks 00J7] setOf_isMaximal_finite : {I : Ideal R | I.IsMaximal}.Finite := by have ⟨s, H⟩ := Finset.exists_inf_le (Subtype.val (p := fun I : Ideal R ↦ I.IsMaximal)) refine Set.finite_def.2 ⟨s, fun p ↦ ?_⟩ have ⟨q, hq1, hq2⟩ := p.2.isPrime.inf_le'.mp (H p) rwa [← Subtype.ext <| q.2.eq_of_le p.2.ne_top hq2]
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
setOf_isMaximal_finite
null
isField_of_isDomain [IsDomain R] : IsField R := by refine ⟨Nontrivial.exists_pair_ne, mul_comm, fun {x} hx ↦ ?_⟩ obtain ⟨n, y, hy⟩ := IsArtinian.exists_pow_succ_smul_dvd x (1 : R) replace hy : x ^ n * (x * y - 1) = 0 := by rw [mul_sub, sub_eq_zero] convert hy using 1 simp [Nat.succ_eq_add_one, pow_add, mul_assoc] rw [mul_eq_zero, sub_eq_zero] at hy exact ⟨_, hy.resolve_left <| pow_ne_zero _ hx⟩ /- Does not hold in a commutative semiring: consider {0, 0.5, 1} with ⊔ as + and ⊓ as *, then both {0} and {0, 0.5} are prime ideals. -/
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isField_of_isDomain
null
isMaximal_of_isPrime {R : Type*} [CommRing R] (p : Ideal R) [p.IsPrime] [IsArtinianRing R] : p.IsMaximal := Ideal.Quotient.maximal_of_isField _ (isField_of_isDomain _)
instance
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isMaximal_of_isPrime
null
isPrime_iff_isMaximal (p : Ideal R) : p.IsPrime ↔ p.IsMaximal := ⟨fun _ ↦ isMaximal_of_isPrime p, fun h ↦ h.isPrime⟩
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isPrime_iff_isMaximal
null
@[simps] primeSpectrumEquivMaximalSpectrum : PrimeSpectrum R ≃ MaximalSpectrum R where toFun I := ⟨I.asIdeal, isPrime_iff_isMaximal I.asIdeal |>.mp I.isPrime⟩ invFun I := ⟨I.asIdeal, isPrime_iff_isMaximal I.asIdeal |>.mpr I.isMaximal⟩
def
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
primeSpectrumEquivMaximalSpectrum
The prime spectrum is in bijection with the maximal spectrum.
primeSpectrumEquivMaximalSpectrum_comp_asIdeal : MaximalSpectrum.asIdeal ∘ primeSpectrumEquivMaximalSpectrum = PrimeSpectrum.asIdeal (R := R) := rfl
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
primeSpectrumEquivMaximalSpectrum_comp_asIdeal
null
primeSpectrumEquivMaximalSpectrum_symm_comp_asIdeal : PrimeSpectrum.asIdeal ∘ primeSpectrumEquivMaximalSpectrum.symm = MaximalSpectrum.asIdeal (R := R) := rfl
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
primeSpectrumEquivMaximalSpectrum_symm_comp_asIdeal
null
primeSpectrum_asIdeal_range_eq : range PrimeSpectrum.asIdeal = (range <| MaximalSpectrum.asIdeal (R := R)) := by simp only [PrimeSpectrum.range_asIdeal, MaximalSpectrum.range_asIdeal, isPrime_iff_isMaximal] variable (R)
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
primeSpectrum_asIdeal_range_eq
null
setOf_isPrime_finite : {I : Ideal R | I.IsPrime}.Finite := by simpa only [isPrime_iff_isMaximal] using setOf_isMaximal_finite R
lemma
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
setOf_isPrime_finite
null
@[local instance] noncomputable fieldOfSubtypeIsMaximal (I : MaximalSpectrum R) : Field (R ⧸ I.asIdeal) := Ideal.Quotient.field I.asIdeal
def
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
fieldOfSubtypeIsMaximal
A temporary field instance on the quotients by maximal ideals.
noncomputable quotNilradicalEquivPi : R ⧸ nilradical R ≃+* ∀ I : MaximalSpectrum R, R ⧸ I.asIdeal := let f := MaximalSpectrum.asIdeal (R := R) .trans (Ideal.quotEquivOfEq <| ext fun x ↦ by rw [PrimeSpectrum.nilradical_eq_iInf, iInf, primeSpectrum_asIdeal_range_eq]; rfl) (Ideal.quotientInfRingEquivPiQuotient f <| fun I J h ↦ Ideal.isCoprime_iff_sup_eq.mpr <| I.2.coprime_of_ne J.2 <| fun hIJ ↦ h <| MaximalSpectrum.ext hIJ)
def
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
quotNilradicalEquivPi
The quotient of a commutative Artinian ring by its nilradical is isomorphic to a finite product of fields, namely the quotients by the maximal ideals.
noncomputable equivPi [IsReduced R] : R ≃+* ∀ I : MaximalSpectrum R, R ⧸ I.asIdeal := .trans (.symm <| .quotientBot R) <| .trans (Ideal.quotEquivOfEq (nilradical_eq_zero R).symm) (quotNilradicalEquivPi R)
def
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
equivPi
A reduced commutative Artinian ring is isomorphic to a finite product of fields, namely the quotients by the maximal ideals.
isSemisimpleRing_of_isReduced [IsReduced R] : IsSemisimpleRing R := (equivPi R).symm.isSemisimpleRing
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isSemisimpleRing_of_isReduced
null
isSemisimpleRing_iff_jacobson : IsSemisimpleRing R ↔ Ring.jacobson R = ⊥ := IsArtinian.isSemisimpleModule_iff_jacobson R R
theorem
RingTheory
[ "Mathlib.Algebra.Group.Units.Opposite", "Mathlib.Algebra.Regular.Opposite", "Mathlib.Data.SetLike.Fintype", "Mathlib.Order.Filter.EventuallyConst", "Mathlib.RingTheory.Ideal.Prod", "Mathlib.RingTheory.Ideal.Quotient.Operations", "Mathlib.RingTheory.Jacobson.Semiprimary", "Mathlib.RingTheory.Nilpotent....
Mathlib/RingTheory/Artinian/Module.lean
isSemisimpleRing_iff_jacobson
null